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Process interactions on catenas have supported grazing adapted ecosystems and sustained biodiversity values in the source zone of the Yellow River in western China for millennia. In recent decades, anthropogenic disturbance and climate change have threatened the integrity of these systems, impacting upon environmental values and their capacity to sustain local livelihoods. Collaborations between local experts and a team of international researchers during a workshop and field excursion to this area in July 2019 developed a cross-disciplinary, process-based model of alpine meadow catenas. This paper relates the contemporary health of these grassland-wetland systems to their 'best achievable state' under prevailing boundary conditions, differentiating stages of degradation and recovery in relation to climate and land use changes. Recovery is underway for alpine meadow catenas at Maqin. Reduced land use pressures (stocking rates) and longer growing seasons have enhanced grassland-wetland conditions. However, recovery prospects are limited for local areas of extremely degraded grasslands (heitutan), as breached abiotic thresholds have resulted in soil and nutrient loss and reduced capacity for water retention. While lagomorphs and rodents act as ecosystem engineers when alpine meadows are in a healthy state, irruptions locally increase the proportion of bare ground and inhibit recovery potential. Management options that support recovery of alpine meadows are presented for differing stages of degradation. [ABSTRACT FROM AUTHOR]

Contrasting landscape and climate settings generate different catenas for alpine steppe grasslands at Maduo (4200 m asl) and alpine meadow grasslands at Maqin (3750 m asl) on the Qinghai-Tibet Plateau. These place-based catenal models can be used as transferable archetypes in environmental management. [Display omitted] • Catenal models are developed for alpine steppe and alpine meadow grasslands on the QTP. • Implications for the generalised use of place-based catenal models are explored. • Research needs and management applications of the catenal models are scoped. Careful development of place-based catenal models and their application as transferable archetypes provides an integrative and generalisable framework for scientifically-informed approaches to environmental management. A workshop and field excursion to the Source Zone of the Yellow River in western China in July 2019 brought together local experts and a team of international researchers to co-develop cross-disciplinary, process-based catenal models that summarise controls on the character and behaviour of grassland environments in alpine meadow (3800 m asl) and alpine steppe (4200 m asl) landscapes. Water, sediment and nutrient fluxes, soil material properties, ground cover (especially percentage bare ground) and the role of small mammals (especially pika) are critical drivers of process linkages in the catenal models. Geologic, climatic and anthropogenic controls on these drivers vary in alpine steppe and alpine meadow settings. While these process interactions have supported grazing adapted ecosystems and sustained biodiversity values in this area for millennia, anthropogenic and climate change disturbances threaten the integrity of these landscapes and their capacity to provide ecosystem services and sustain livelihoods into the future. The place-based catenal models presented in this paper can be used to support applications that appropriately target key attributes, linkages and fluxes that may require conservation, maintenance or treatment in the management of alpine steppe and alpine meadow landscapes. [ABSTRACT FROM AUTHOR]